I figured I'd throw out a recommendation for a server room temperature monitoring tool I've used for several months now. I had a client buy a USB temperature monitoring kit + 1 additional USB gateway, and for about $250 (includes 1 year of their $39/yr. premier subscription) total I am able to monitor two separate server rooms in two different buildings and get alerts. The alerting comes from their servers and you can check the status via web portal or even a mobile app. I have used their tech support a couple of times and it's U.S. based and excellent.
http://www.monnit.com/ I am not uncompensated for this pitch and I am unaffiliated with them, but I did stay at a Holiday Inn Express once.
